add support to redact (hide) some of the labels in the metrics

README.md

@@ -114,6 +114,9 @@ For a more realistic example please have a look at [examples/kubernetes/configma
 
 ```yaml
 ---
+# redacted_labels contains the list of standard labels you can hide from the generated
+# metrics, it supports the values: "host", "database", "user"
+redacted_labels: []
 # jobs is a map of jobs, define any number but please keep the connection usage on the DBs in mind
 jobs:
   # each job needs a unique name, it's used for logging and as a default label

config.go

@@ -26,14 +26,8 @@ func getenv(key, defaultVal string) string {
 }
 
 var (
-	metricsPrefix = "sql_exporter"
-	failedScrapes = prometheus.NewGaugeVec(
-		prometheus.GaugeOpts{
-			Name: fmt.Sprintf("%s_last_scrape_failed", metricsPrefix),
-			Help: "Failed scrapes",
-		},
-		[]string{"driver", "host", "database", "user", "sql_job", "query"},
-	)
+	metricsPrefix             = "sql_exporter"
+	failedScrapes             *prometheus.GaugeVec
 	tmplStart                 = getenv("TEMPLATE_START", "{{")
 	tmplEnd                   = getenv("TEMPLATE_END", "}}")
 	reEnvironmentPlaceholders = regexp.MustCompile(
@@ -55,11 +49,10 @@ var (
 	DefaultQueryDurationHistogramBuckets = prometheus.DefBuckets
 	// To make the buckets configurable lets init it after loading the configuration.
 	queryDurationHistogram *prometheus.HistogramVec
-)
 
-func init() {
-	prometheus.MustRegister(failedScrapes)
-}
+	// globally redacted labels, those labels will be hidden from every metrics
+	redactedLabels []string
+)
 
 // Read attempts to parse the given config and return a file
 // object
@@ -118,6 +111,7 @@ type File struct {
 	Jobs           []*Job            `yaml:"jobs"`
 	Queries        map[string]string `yaml:"queries"`
 	CloudSQLConfig *CloudSQLConfig   `yaml:"cloudsql_config"`
+	RedactedLabels []string          `yaml:"redacted_labels"` // globally redacted labels
 }
 
 type Configuration struct {

config.yml.dist

@@ -1,4 +1,6 @@
 ---
+# supports "host", "database", "user"
+redacted_labels: []
 jobs:
 - name: "global"
   interval: '5m'

examples/kubernetes/configmap.yml

@@ -6,6 +6,7 @@ metadata:
 data:
   config.yml: |
     ---
+    redacted_labels: []
     jobs:
     - name: "master-nodes"
       interval: '1m'
@@ -127,7 +128,7 @@ data:
         values:
           - "replication_lag"
         query:  |
-                WITH lag AS ( 
+                WITH lag AS (
                 SELECT
                   CASE
                     WHEN pg_last_xlog_receive_location() = pg_last_xlog_replay_location() THEN 0

exporter.go

@@ -36,6 +36,17 @@ func NewExporter(logger log.Logger, configFile string) (*Exporter, error) {
 		return nil, err
 	}
 
+	// initialize global variables failedScrapes and redactedLabels
+	redactedLabels = cfg.RedactedLabels
+	failedScrapes = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: fmt.Sprintf("%s_last_scrape_failed", metricsPrefix),
+			Help: "Failed scrapes",
+		},
+		GetLabelsForFailedScrapes(),
+	)
+	prometheus.MustRegister(failedScrapes)
+
 	var queryDurationHistogramBuckets []float64
 	if len(cfg.Configuration.HistogramBuckets) == 0 {
 		queryDurationHistogramBuckets = DefaultQueryDurationHistogramBuckets

job.go

@@ -11,23 +11,22 @@ import (
 	"time"
 
 	_ "github.com/ClickHouse/clickhouse-go/v2" // register the ClickHouse driver
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/rds/rdsutils"
 	"github.com/cenkalti/backoff"
-	_ "github.com/microsoft/go-mssqldb" // register the MS-SQL driver
-	_ "github.com/microsoft/go-mssqldb/integratedauth/krb5" // Register integrated auth for MS-SQL
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/go-sql-driver/mysql" // register the MySQL driver
 	"github.com/gobwas/glob"
 	"github.com/jmoiron/sqlx"
-	_ "github.com/lib/pq" // register the PostgreSQL driver
+	_ "github.com/lib/pq"                                   // register the PostgreSQL driver
+	_ "github.com/microsoft/go-mssqldb"                     // register the MS-SQL driver
+	_ "github.com/microsoft/go-mssqldb/integratedauth/krb5" // Register integrated auth for MS-SQL
 	"github.com/prometheus/client_golang/prometheus"
 	_ "github.com/segmentio/go-athena" // register the AWS Athena driver
 	"github.com/snowflakedb/gosnowflake"
 	_ "github.com/vertica/vertica-sql-go" // register the Vertica driver
 	sqladmin "google.golang.org/api/sqladmin/v1beta4"
-
-	"github.com/aws/aws-sdk-go/aws/session"
-	"github.com/aws/aws-sdk-go/service/rds/rdsutils"
 )
 
 var (
@@ -101,7 +100,7 @@ func (j *Job) Init(logger log.Logger, queries map[string]string) error {
 		q.desc = prometheus.NewDesc(
 			name,
 			help,
-			append(q.Labels, "driver", "host", "database", "user", "col"),
+			append(q.Labels, GetLabelsForSQLGauges()...),
 			prometheus.Labels{
 				"sql_job": j.Name,
 			},
@@ -313,7 +312,7 @@ func (j *Job) updateConnections() {
 						level.Error(j.log).Log("msg", "You cannot use exclude and include:", "url", conn, "err", err)
 						return
 					} else {
-						extractedPath := u.Path //save pattern
+						extractedPath := u.Path // save pattern
 						u.Path = "/postgres"
 						dsn := u.String()
 						databases, err := listDatabases(dsn)
@@ -497,7 +496,7 @@ func (j *Job) runOnceConnection(conn *connection, done chan int) {
 
 func (j *Job) markFailed(conn *connection) {
 	for _, q := range j.Queries {
-		failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+		failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 	}
 }
 

labels.go

@@ -0,0 +1,70 @@
+package main
+
+import "slices"
+
+func GetLabelsForFailedScrapes() []string {
+	standardLabels := [6]string{"driver", "host", "database", "user", "sql_job", "query"}
+	var labels []string
+	for _, l := range standardLabels {
+		if !slices.Contains(redactedLabels, l) {
+			labels = append(labels, l)
+		}
+	}
+
+	return labels
+}
+
+func GetLabelsForSQLGauges() []string {
+	standardLabels := [5]string{"driver", "host", "database", "user", "col"}
+	var labels []string
+	for _, l := range standardLabels {
+		if !slices.Contains(redactedLabels, l) {
+			labels = append(labels, l)
+		}
+	}
+
+	return labels
+}
+
+func AppendLabelValuesForSQLGauges(labels []string, conn *connection, valueName string) []string {
+	labels = append(labels, conn.driver)
+
+	if !slices.Contains(redactedLabels, "host") {
+		labels = append(labels, conn.host)
+	}
+
+	if !slices.Contains(redactedLabels, "database") {
+		labels = append(labels, conn.database)
+	}
+
+	if !slices.Contains(redactedLabels, "user") {
+		labels = append(labels, conn.user)
+	}
+
+	labels = append(labels, valueName)
+
+	return labels
+}
+
+func FilteredLabelValuesForFailedScrapes(conn *connection, q *Query) []string {
+	var labels []string
+
+	labels = append(labels, conn.driver)
+
+	if !slices.Contains(redactedLabels, "host") {
+		labels = append(labels, conn.host)
+	}
+
+	if !slices.Contains(redactedLabels, "database") {
+		labels = append(labels, conn.database)
+	}
+
+	if !slices.Contains(redactedLabels, "user") {
+		labels = append(labels, conn.user)
+	}
+
+	labels = append(labels, q.jobName)
+	labels = append(labels, q.Name)
+
+	return labels
+}

query.go

@@ -33,7 +33,7 @@ func (q *Query) Run(conn *connection) error {
 	now := time.Now()
 	rows, err := conn.conn.Queryx(q.Query)
 	if err != nil {
-		failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+		failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 		failedQueryCounter.WithLabelValues(q.jobName, q.Name).Inc()
 		return err
 	}
@@ -48,25 +48,25 @@ func (q *Query) Run(conn *connection) error {
 		err := rows.MapScan(res)
 		if err != nil {
 			level.Error(q.log).Log("msg", "Failed to scan", "err", err, "host", conn.host, "db", conn.database)
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 			continue
 		}
 		m, err := q.updateMetrics(conn, res, "", "")
 		if err != nil {
 			level.Error(q.log).Log("msg", "Failed to update metrics", "err", err, "host", conn.host, "db", conn.database)
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 			continue
 		}
 		metrics = append(metrics, m...)
 		updated++
-		failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(0.0)
+		failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(0.0)
 	}
 
 	if updated < 1 {
 		if q.AllowZeroRows {
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(0.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(0.0)
 		} else {
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 			failedQueryCounter.WithLabelValues(q.jobName, q.Name).Inc()
 			return fmt.Errorf("zero rows returned")
 		}
@@ -106,7 +106,7 @@ func (q *Query) RunIterator(conn *connection, ph string, ivs []string, il string
 	for _, iv := range ivs {
 		rows, err := conn.conn.Queryx(q.ReplaceIterator(ph, iv))
 		if err != nil {
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 			failedQueryCounter.WithLabelValues(q.jobName, q.Name).Inc()
 			return err
 		}
@@ -117,18 +117,18 @@ func (q *Query) RunIterator(conn *connection, ph string, ivs []string, il string
 			err := rows.MapScan(res)
 			if err != nil {
 				level.Error(q.log).Log("msg", "Failed to scan", "err", err, "host", conn.host, "db", conn.database)
-				failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+				failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 				continue
 			}
 			m, err := q.updateMetrics(conn, res, iv, il)
 			if err != nil {
 				level.Error(q.log).Log("msg", "Failed to update metrics", "err", err, "host", conn.host, "db", conn.database)
-				failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(1.0)
+				failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(1.0)
 				continue
 			}
 			metrics = append(metrics, m...)
 			updated++
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(0.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(0.0)
 		}
 	}
 
@@ -137,7 +137,7 @@ func (q *Query) RunIterator(conn *connection, ph string, ivs []string, il string
 
 	if updated < 1 {
 		if q.AllowZeroRows {
-			failedScrapes.WithLabelValues(conn.driver, conn.host, conn.database, conn.user, q.jobName, q.Name).Set(0.0)
+			failedScrapes.WithLabelValues(FilteredLabelValuesForFailedScrapes(conn, q)...).Set(0.0)
 		} else {
 			return fmt.Errorf("zero rows returned")
 		}
@@ -237,7 +237,7 @@ func (q *Query) updateMetric(conn *connection, res map[string]interface{}, value
 	}
 	// make space for all defined variable label columns and the "static" labels
 	// added below
-	labels := make([]string, 0, len(q.Labels)+5)
+	labels := make([]string, 0, len(q.Labels)+(5-len(redactedLabels)))
 	for _, label := range q.Labels {
 		// append iterator value to the labels
 		if label == il && iv != "" {
@@ -262,11 +262,9 @@ func (q *Query) updateMetric(conn *connection, res map[string]interface{}, value
 		}
 		labels = append(labels, lv)
 	}
-	labels = append(labels, conn.driver)
-	labels = append(labels, conn.host)
-	labels = append(labels, conn.database)
-	labels = append(labels, conn.user)
-	labels = append(labels, valueName)
+
+	labels = AppendLabelValuesForSQLGauges(labels, conn, valueName)
+
 	// create a new immutable const metric that can be cached and returned on
 	// every scrape. Remember that the order of the label values in the labels
 	// slice must match the order of the label names in the descriptor!